Field of the Invention
The present invention relates to a method of manufacturing a gasket which is integrated with a substrate by using a metal mold.
Description of the Conventional Art
For example, a fuel battery is provided with a substrate integrated gasket obtained by integrally bonding a gasket 2 made of a rubber elastic body (a rubber material or a synthetic resin material having a rubber-like elasticity) with a substrate 1 such as a separator corresponding to a constructing part of the fuel battery cell, as shown in FIG. 6, as a means for sealing fuel gas or oxidation gas. Further, the structure in which the gasket 2 is integrally bonded with the substrate 1 via an adhesive agent layer 3 has been known as this kind of substrate integrated gasket.
FIG. 7 shows a typical prior art of the method of manufacturing the substrate integrated gasket as mentioned above. More specifically, in the manufacturing method, the substrate 1 having the adhesive agent layer 3 previously formed on a surface thereof by application of the adhesive agent is first of all positioned and fixed between metal molds 101 and 102, a liquid-like rubber is injected into a gasket forming cavity 103 which is defined between the adhesive agent layer 3 on the surface of the substrate 1 and an inner surface of the one metal mold 101 according to a method such as a liquid injection molding (LIM) method, and the gasket is integrally bonded with the substrate 1 via the adhesive agent layer 3 at the same time of forming the gasket by crosslinking and curing on the basis of a thermal reaction (refer, for example, to the Japanese Unexamined Patent Publication No. 2008-168448).
However, according to the conventional method of manufacturing the substrate integrated gasket, a mold clamping surface 101a in the periphery of the cavity 103 in the metal mold 101 comes to a state in which the mold clamping surface 101a is closely attached to the adhesive agent layer 3 on the surface of the substrate 1 at the mold clamping time shown in FIG. 7. As a result, in order to prevent defective molding caused by residual air within the cavity 103, it is necessary to provide a desired number of air vents (not shown) extending from the cavity 103 in the metal mold 101. Therefore, a post-process for removing burrs constructed by cured materials of the liquid rubber flowing into the air vents has been necessary after completion of the molding.
The present invention has been made by taking the above points into consideration, and a technical object of the present invention is to provide a method of manufacturing a substrate integrated gasket which can make the provision of the air vents extending from the cavity in the metal mold unnecessary and can therefore make the post-process for removing the burrs formed within the air vents unnecessary.